This filter is primarily designed for use between the antenna and a receiver/scanner, although it can find its use in many other applications. It combines a passive high pass filter that greatly attenuates all signals below 30 MHz and a passive notch filter that suppresses the strong signals from the VHF FM broadcast band by at least 30dB.

It passes all signals from 31 to 80 MHz and from 118 to 1600 MHz with a negligeable insertion loss below 1dB. Hence it is an ideal accessory for all hand held and table top scanners (Yupiteru, Alinco, AOR, ICOM, YAESU, Uniden-Bearcat etc.). Its BNC coax connectors simply fit onto the antenna input connector and the antenna is connected to the BNC connector of the filter.

The filter finds its use at places with strong broadcast signals from LW, MW and SW bands and especially from VHF FM band. These signals very often cause overloading of the receiver front end and hence significant deterioration of sensitivity. With the filter it is then not necessary to use the attenuator of the receiver to get rid of the interference and overloading, so the receiver sensitivity is maintained. The filter eliminates all the interference from all the bands below 30 MHz, including CB. This filter also improves reception in the air-band which is close to the VHF FM band. The filter has been tested at places close to 100kW broadcast transmitters when even top class scanners like ICOM IC-R8500 or AOR AR-5000 suffer from overloading in the air-band. The filter enables clear reception at such difficult locations.

It may reduce image reception of signals from VHF FM band. It can also be used between a wide band antenna, such as discone, vertical or log-periodic, and a pre-amplifier, which will reduce the overloading of the wide band preamp.

This filter is exactly what I needed to drop the SW and FM noise out of my scanners. The product worked perfectly and dropped the noise level and out of band interference by 30db as designed. Thank You for providing this combination filter as usually you can only find filters that work on one bad at a time..

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Does what it claims

August 31, 2015

Reviewer:
Johnnydollar2 from Chicago-land

Have had it for awhile now with my WS1080 here in FM -front-end interference land of Chicago. They could rename our area "Overload" This combined notch filter did a good job cleaning up the noise. I'm getting more frequencies in the 155.000 and 470.000 range without hash and noise that reminds me of the old "eat at joes!" neon signs. Used with a variety of antennas and it does a good job.

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1 of 1 people found the following review helpful:

HPN-30118

August 28, 2015

Reviewer:
Paulo Rossi from Maringa, Parana Brazil

Very nice notch filter, thank you.

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2 of 2 people found the following review helpful:

tested on FM band & works great!

March 26, 2014

Reviewer:
Anonymous Person from Orlando, FL United States

I bought this notch filter to use in conjunction with my Optoelectronics Xplorer (near field receiver) and it did a great job of eliminating interference/overload from local FM radio stations, increasing sensitivity to distant & lower power transmissions